Overheating on 1991 Ford Escort

This car has been a great little car however I have always had periodic overheating problems and am now experiencing the same. Recently had water pump and thermostat replaced - solved problem for about a year but overheating coming back. Have flushed the radiator, cleaned the reserve, cleaned the outside of the radiator with a brush & hose and still the problem persists. Suggestions?

If your cooling fan is operating properly , then you may have a restriction of flow through the radiator. To test the cooling fan, start the motor and let the vehicle warm up, the fan should come after awhile, if it does not and the temperature gauge rises to 3/4, turn on the AC. As soon as the AC comes on the cooling fan should start to run and the temperature gauge should go down . Unfortunately, this test only works when the AC system is fully charged and operational. With higher mileage vehicles the cooling tubes in the radiator core get plugged with mineral deposits and this reduces the affective cooling capacity of the radiator. Flushing does not get rid of these deposits. In the past you could have the radiator disassembled and rodded (running a metal rod into each radiator core tube until the tube was clean. Unfortunately, current radiators tanks are made of plastic with aluminum cores that are not usually disassembled for rodding. One way to check the flow rate through radiator is to install a flowmeter in the series with a coolant hose, but there are not many places that have this flowmeter. You can test it by letting the motor run until the temperature gauge reaches normal operating and the cooling fan comes on, then touch the front of the radiator core (on the front side away from the cooling fan) and see if the whole core is the same temperature(Caution the radiator core temp can exceed 220 degrees F). If some areas are cooler than others then it is most likely restricted and you will need to replace it. Good luck.